BOUNDARY VALUE PROBLEMS IN A SEMI-INFINITE PARALLELEPIPED FOR AN ELLIPTIC EQUATION WITH THREE SINGULAR COEFFICIENTS. Scientific journal of the Fergana State University, [S. l.], n. 2, p. 11–23, 2023. Disponível em: https://journal.fdu.uz/index.php/sjfsu/article/view/376. Acesso em: 10 jan. 2026.